CZ302296A3 - Cylinder head gasket - Google Patents

Abstract

The present invention relates to a cylinder head gasket for internal combustion engines. According to the invention, the gasket comprises a laminate which consists in a thin stainless steel plate or a heat-resistant steel plate that is coated on each side with still thinner carrier-calendared rubber films which have a thickness of at least 0.05 mm and which are affixed to the steel plate by vulcanization. The steel plate suitably has a thickness of about 0.2 to 0.4 mm and the rubber films each have a thickness of at least 0.05 to 0.20 mm.

Description

Field of the invention

The present invention relates to a gasket, a cylinder head gasket for internal combustion engines.

especially then

Raising the snakes 35 SXiSCSjl> udca.

NE aZ ku several zen ~ fi. y l o ΐ ány dohromacy. boards. which can colors, or rubber -. ve zori N E 27 0 —O \ U Cl ( IN patent steed! head cylinders that cover a layer of rubber;

^The viscous can be applied from SS3Z1 with an extremely thin seal layer in the form of a solution and then heated to remove the solvents and to form the layer. Previous patent applications DE-C2-3500071 and JP-A-62/101873 also disclose cylinder head gaskets of this kind that are produced from various types of rubber solutions. US-A-5110530 discloses the manufacture of a gasket formed of a thin metal strip, which is successively treated with chromate and rubber adhesive during a continuous process, followed by heat treatment of the gasket, after which a rubber layer is applied. The desired thickness is affected by the application of an adhesive layer. Thus, the laminate will have an adhesive layer between each rubber layer and the metal surface.

In many cases, the use of today's cylinder head gaskets is problematic, especially when used in engines in which the cylinder head and engine block are made of different materials, which will become more and more common in the coming years. For example, it is common to produce an aluminum alloy cylinder head and a cast iron engine block. As a result of the different thermal properties of the materials, transverse movements occur between the cylinder head and the engine block while the engine is running.

This increases the requirements for cylinder head gasket to withstand the shearing forces to which it is subjected as a result of thermal forced transverse movements. One solution would be to increase the amount of metal layers in the seal. However, this solution cannot be considered final, for somewhat different reasons. First, the more complex design of the cylinder head gasket will, of course, be more expensive, since both material costs and production costs will greatly increase. The second cause is environmental. The thicker the seal, the more likely it is that the seal formed will cause a higher concentration of unburnt hydrocarbons in the exhaust gas, and the consequence of this is very problematic in view of current environmental considerations.

Thus, the ideal cylinder head gasket material for modern internal combustion engines should exhibit good shear resistance properties and its ability to absorb shear forces while being thin and easy to manufacture, while still having effective resistance to explosive atmospheres. in this context, i.e. the tightness of the cylinder head gasket prevails with respect to the use of:

which is particularly important in it should provide the best under the difficult conditions of those cylinder head gaskets.

SUMMARY OF THE INVENTION

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a cylinder head gasket that will fully meet the above-mentioned high requirements for dreaming for modern combustion engines that operate under operating conditions.

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The cylinder head gasket of the invention is thus characterized in that the cylinder heads are made of stainless steel. thin steel plates and / or heat-resistant steel plates. The latter is coated on its sides with an even thinner carrier rubber film having a thickness of at least 0.05 mm a. je__nanesep. to a steel plate by means of a vulcanization process.

The stainless steel and / or heat resisting steel forming the steel plates will suitably have a thickness of 0.2 to 0.4 mm and each of the rubber layers will preferably have a thickness of 0.05 to 0.20 mm. The outer surface of the rubber layer will suitably have a textile backing structure, preferably a roughened or "blistered" structure. ...

The specific combination of features defined in the claims gives the laminate a unique combination of being compressible, having good ability to absorb shear forces and explosive resistance

environment (seals; 1 capability), as mentioned above. Therefore, it is important so that the rubber coating has these specific Features and make specific structure that is manifested arranged rubber layers, among other things such as homogeni and uniformity with regard to physical properties and cut measure, and that will be free of pores in such quality in which t; z will only be possible. These properties cannot be achieved ug ^- of a grain coating that has been applied in the not in the form of a solution; in the form of a paste that has been applied

roller directly r.A plate or not the surface of the substrate,

because rubber oc. ; _a; <or wound created by usίι · η_ο zpusooem, will always be b s and h c Whether residual paste forming elements, or residues dissolve ei that result in the formation of cores and others en.it and therefore cause weakened zones as well as m.Oi.ny zr. acnezuvnucn layers. is also culezute, i ct 7 2s o i and was applied to the plate with the aid of carrier that harnesses .highly effective and, above all, even adhesion

inequalities on; surface, and rcvnsz enable, aoy : f outer surface r the structure that is appropriate is given the carrier selected. The surface structure obtained at or vulcanizing the textile carrier, for example with a so-called plate structure is particularly advantageous. Surprisingly it was from assured that it is rough or “blistered

the outer surface structure provides improved bearing surface and improved sealing on contact with metal surfaces.

Material that m = these qualities can also be effective fastened with vulcanization with respect to mechanical strength joints rubber -plate. Production method using carriers a. belt vulcanif machines is the same as the one has been described of our previously published patent applications

applications, 91/13758).

for example in the application

EP - A - 594S01 (WO

The invention will now be described in the above paragraphs, with respect to describing various tests of which material.

somewhat more in detail below for a few examples that have been made on the used

DETAILED DESCRIPTION OF THE INVENTION

Example 1

The laminate consists of a pad made of stainless steel with a thickness of selaortelnosci, a tiouscce of 0.20 mm and two cumulative layers l »-r ·

0.08 mm., This assembly was below: in accordance with the following:

The package, consisting of ten 40 x 40 mm material samples, was subjected to a pressure of 16.5 MPa with a force of 2.4 kN at room temperature. This was repeated seven times, maintaining the pressure for one second. A package of laminated samples was found to be compressed by 16. µm, which corresponds to a specific compressibility of 2 µm / 10 MPa.

Example 2

The test was carried out on a 4 cylinder engine with a displacement of 2000 cm ³ , with a 16-valve fuel injection system, type SAAB 9000, for twenty-four hours ... The engine was modified by lowering the piston heads to allow implement a thinner cylinder head gasket formed from the above laminate.

The gasket was made of one sample of laminate, consisting of a layer of stainless steel

0.08 mm thick rubber layer, 0.2 mm thick: made of one more thick rubber layer

0,03 mm. The rubber was in quality Rubore EGM-1-ST.

The engine was tested in accordance with a test program that simulated engine running on a motorway, including long periods of full-power at maximum rpm and maximum torque, these periods were interleaved by moderate load periods at which the engine and interrupted he ran at idle at thirty minute intervals.

Thereafter, the motor was not seen to be normal during this period.

no no function of suitable gasket effects of cylinder head running

Claims (4)

1.) Cylinder head gasket for internal combustion engines, characterized in that the gasket consists of a laminate consisting of a thin stainless steel plate or a thin heat-resistant steel plate coated with an even thinner layer of rubber film arranged on its sides by means of a carrier, both of these rubber films having a thickness of at least 0.05 mm and both are applied to the steel plates by vulcanization, 2.) Cylinder head gasket for internal combustion engines according to claim 1, characterized in that the steel plate has a thickness in the range. 0.2 mm to 0.4 mm and each of the rubber films has a thickness ranging from 0.05 mm to 0.20 mm. Cylinder head gasket according to claim 1 or claim 2, characterized in that the outer surface of the rubber films has a textile support structure, and preferably a roughened or blistered structure. Use of a cylinder head gasket for internal combustion engines according to claim 1-, according to claim 2 and according to claim 3, characterized in that the seal consists of: ·. :. . They are comprised of a number of laminate layers which have been bonded together by vulcanization.